I wish that there was a simple, single answer for this. There's only one thing more distressing - no device recognition at all. Here are the most likely culprits:

* The USB device or the USB adapter requires it's own power source. If your USB device or adapter came with an AC power "brick", try connecting it. * Here's a likely one - the front USB ports on your PC case may be misconnected. I've seen them that way from the factory. It's a good idea to check the connections against specifications. The standard order of connection is Red, White, Green, Black. No more than 4 wires per USB bank are needed. * Defective device. Do not assume that all PC components work correctly out of the box. I've seen many new USB devices that do not work. If you can, try the device on another PC. * All drivers are not installed. Some devices will require installing the driver package before plugging in the device. Some devices will also require basic USB files from the Windows CD before the unit will function. The general rule is to always follow installation directions precisely and to have the Windows CD ready.

I will now discuss how to address an unknown device problem which is caused by a driver deficiency.

1. Try to update the unknown device driver from within Device Manager. First try letting Windows search for one. If that fails, go back and choose "Select from a list" and then "Have disk". Browse to the device CD and look for the appropriate Windows folder there. Try browsing to the Windows CD (Win9x folder or i386 folder). Lastly, try updated drivers from the manufacturer's web site. 2. Try uninstalling the unknown device, unplugging the device and rebooting. Replug when back in Windows. 3. Be certain that you have the correct drivers! You may have gotten the wrong CD or a CD with drivers for more than one device on it. 4. Cleaning up in Safe Mode may be necessary. Unplug all USB devices. Reboot the PC. To enter Safe Mode, press the F8 key repeatedly while restarting the PC. Timing is important. Try to press quickly before the Windows logo screen appears. Pressing and holding the CTRL key may work too. Choose Safe Mode and open Device Manager. In Windows 2000 and XP, click View > Show hidden devices. Now locate all USB devices, HID (Human Interface Devices), USB drives and controllers/hubs. Remove all and save the USB Host Controllers for last. When done, restart and replug USB devices one at a time.

Just remember that you are entitled to support from the device maker. If you can't get help, do not hesitate to return the device. Some manufacturers only seem to respond to lost business. It's a shame, but it's true. Send them a message - that you won't accept shoddy goods or lackluster support.

Reset the power module and test the power
Step one: Reset the power moduleThe power module has a safety feature inside that protects the product during a power surge. If you experienced a recent power surge, the power module might need to be reset. Use the following steps to reset the power module.

Unplug the power supply from the rear of the product.

Unplug the power cord from the electrical outlet, power strip, or surge protector.

If the product uses a power module with a detachable power cord, disconnect the cord from the power module.

Wait 15 seconds.

Reconnect the power cord to the power module.

Plug the power cord back into the electrical outlet. Do not use a power strip or surge protector.

Check to see if the power module has an LED.

If the power module does not have an LED, continue to the next step.

If the power module has an LED, check to see if the LED lights up.

If the LED does not light up, contact HP to replace the power module. To buy a compatible power module, right-click the following link, How to Buy HP , and then click Open in New Window .

If the LED lights up, continue to the next step.

Step two: Test the power on the All-in-OneFollow these steps to test the power on the product.

Reconnect the power supply to the rear of the product.

Press and quickly release the Power button ( ) to start a Power On/Off cycle. Do not hold the button down.
Figure 1: Press and quickly release the Power button
If you press and hold the Power button too long, the product might turn on and then off without restarting. If this happens, press and quickly release the Power button ( ) again.

If these steps resolved the issue , there is no need to continue troubleshooting.

If the issue persists , see the next step.

Solution four: Test the power with a compatible power cord from a different product
If you have another available power cord that is compatible with your product, use the alternate cord to repeat the steps in Solution three: Reset the power module and test the power .

If the product turns on with the alternate power cord, the original power cord caused the issue. Contact HP to replace the power cord. Right-click the following link, How to Buy HP , to buy a compatible power cord.

If the product does not turn on with the alternate power cord, continue to the next step.

I just posted my problem and found the solution on a different web page. It is this and it WORKS
All you have to do is HOLD DOWN FOUR BUTTONS AT THE SAME TIME: ( OK, Cancel, Black , Color ) and turn the power off. Do this at least twice and the unit will power up and go to maintenance. Then it was back to normal.
HP gives you a procedure that doesn't work! They just want to sell you a new one. They must know the solution if and old woman like me can figure it out with help from other people with the same problem

I would think that a ribbon cable which connects to the display module has been disconneted. Printers are fairly intricate and great care must be taken on dissassembly as well as assembly. Take a look but take care in doing so, its not worth taking them in for repairs these days because printers are cheap to buy and tech labour is not cheap. I have an HP 3630 wireless printer and it does excellent photos transmitted straight from phone on wifi, only cost $70au

First customize the paper size in the Page Setup. Secondly when you send command for print, change the paper size to custom size from the Printer Properties and click print. On the other hand, you can select the paper size from the printer's menu itself after sending the print command. Please make sure that the right driver of the printer is installed on your computer.

Unfortunately, printers seem to have a short life to them.
We had to replace ours and buy new ink cartridges because
they make it to where you have to buy a different cartridge number for the same brand of printer.
How old is the printer? Base your decision on whether to replace it or not. If it is old, the best thing would be to replace it.

Push OK, CANCEL, BLACK, & COLOR all at once while turning the printer off, turn it back on. I had to do this 2 times to get it to work and then it went through a long period of maintanence before I could print

(The obvious) Replace the black cartridge. Even if ot says you have ink you could have a faulty cartridge, even if it has worked fine in the past. (The not so obvious) Clean your printheads/nozzles. Repeat the process a few times.